Serosurvey of Borrelia in dogs, horses, and humans exposed to ticks in a rural settlement of southern Brazil / Soroprevalência e fatores associados a Borrelia em cães, equinos e humanos expostos a carrapatos em um assentamento rural do sul do Brasil

Abstract The aims of the present study were to serosurvey dogs, horses, and humans highly exposed to tick bites for anti-Borrelia burgdorferi s.l. antibodies, identify tick species present, and determine risk factors associated with seropositivity in a rural settlement of Paraná State, southern Brazil. Eighty-seven residents were sampled, along with their 83 dogs and 18 horses, and individual questionnaires were administered. Immunofluorescence antibody test (IFAT) was performed on serum samples and positive samples were subjected to western blot (WB) analysis. Anti-B. burgdorferi antibodies were found in 4/87 (4.6%) humans, 26/83 (31.3%) dogs, and 7/18 (38.9%) horses by IFAT, with 4/4 humans also positive by WB. Ticks identified were mostly from dogs and included 45/67 Rhipicephalus sanguineus, 21/67 Amblyomma ovale, and 1/67 A. cajennense sensu lato. All (34/34) horse ticks were identified as A. cajennense s.l.. No significant association was found when age, gender, or presence of ticks was correlated to seropositivity to Borrelia sp. In conclusion, although anti-Borrelia antibodies have been found in dogs, horses and their owners from the rural settlement, the lack of isolation, molecular characterization, absence of competent vectors and the low specificity of the commercial WB kit used herein may have impaired risk factor analysis.

Resumo Os objetivos do presente estudo foram realizar um levantamento sorológico de cães, cavalos e humanos altamente expostos a picadas de carrapatos para anticorpos anti-B. burgdorferi s.l., identificar as espécies de carrapatos presentes, e determinar os fatores de risco associados a soropositividade em um assentamento rural do Estado do Paraná, sul do Brasil. Oitenta e sete residentes foram amostrados junto com seus respectivos 83 cães e 118 cavalos e questionários individuais foram aplicados. O teste de imunofluorescência indireta (IFI) foi realizado nas amostras sorológicas e as positivas foram submetidas a análise por western blot (WB). Anticorpos anti-B. burgdorferi foram detectados em 4/87 (4,6%) humanos, 26/83 (31,3%) cães e 7/18 (38,9%) cavalos pela IFI, com 4/4 humanos também positivos pelo WB. Os carrapatos identificados foram em sua maioria de cães e incluíram 45/67 Rhipicephalus sanguineus, 21/67 Amblyomma ovale e 1/67 A. cajennense sensu lato. Todos (34/34) carrapatos dos cavalos foram identificados como A. cajennense s.l.. Não foram observadas diferenças estatísticas entre idade, sexo ou presença de carrapatos e soropositividade para Borrelia sp. Em conclusão, embora anticorpos anti-Borrelia tenham sido encontrados em cães, equinos e seus proprietários do assentamento rural, a ausência de isolamento, caracterização molecular, ausência de vetores competentes e baixa especificidade do kit comercial de WB utilizado podem ter limitado a análise de fatores de risco.

Borrelia burgdorferi (strain B. afzelii) antibodies among Malaysian blood donors and patients.

In this study, the presence of IgG and IgM antibodies against Borrelia burgdorferi (strain B. afzelii) among Malaysian blood donors and patients admitted to hospital with various infectious diseases was determined. Sera were screened using enzyme-linked immunosorbent assay (ELISA); positive sera were then subjected to Western blot testing. All but one of the blood donors were negative for borrelial antibodies. Of 121 patients' sera, IgM antibodies were detected in 24 (19.8%) and IgG antibodies were detected in 5 (4.1%) sera. Only one of two patients with skin manifestations suggestive of Lyme disease had IgM antibody against B. afzelii. Of 30 patients with exposure to tick typhus, 4 (13.3%) were IgM positive and 1 (3.3%) was IgG positive. Based on the detection of antigenic bands by Western blot, 6 patients' sera showed positive reactions. Antigenic bands of p39, p41 and p59/62 kDa were the commonest findings of Western blotting. This study provides serological evidence of B. afzelii infections in Malaysia; further investigation is needed to correlate serological and clinical findings.

Distribution of Borrelia burgdorferi specific antibody among patients with juvenile rheumatoid arthritis in Korea

Lyme disease, a multi-systemic infection occurring worldwide, has yet to be reported in Korea, although the spirochete B. burgdorferi, known as the causative organism of the disease, has recently been isolated from the vector tick Ixodes persulcatus in the region. To contribute to revealing whether Lyme disease exists in Korea or not, B. burgdorferi specific antibodies (IgG, IgM, and/or IgA) were measured by three individual enzyme-linked immunosorbent assays (ELISA) utilizing different antigens in 38 patients with juvenile rheumatoid arthritis (JRA) which shares a number of clinical features with Lyme arthritis. The antibody prevalence rates in patients with JRA were various depending on the antigens (21% of IgG and IgM antibodies to purified organisms, 0% for IgG antibody to purified native flagella, and 5% for IgG, IgM, and IgA antibodies to recombinant p39) and were not different compared to 39 controls (21%, 0%, and 0% respectively). The antibody prevalence rates compared in various subgroups of patients with JRA according to types of JRA, length of illness, age, and sex were not different. Comparing the three different antigens, the greatest number of positive responders were yielded by purified organisms followed by p39 and purified flagellin, however the possibility of nonspecificity with purified organisms remained. The data indicate that serologic tests using ELISA fail to illustrate Lyme disease among 38 patients with JRA in Korea.